#include <stdio.h>

int main() {
    int a, b, c;
    while (scanf_s("%d %d %d", &a, &b, &c) != EOF)
    {
        if (a + b > c && b + c > a && a + c > b)
        {
            if (a == b && a == c & b == c)
                printf("Equilateral triangle!\n");
            else if (a == b || a == c || b == c)
                printf("Isosceles triangle!\n");
            else printf("Ordinary triangle!\n");
        }
        else
        {
            printf("Not a triangle!\n");
        }
    }

    return 0;
}